Johnson was called up from Double-A Rocket City and will start Thursday's contest against the Athletics, Rhett Bollinger of MLB.com reports.
Johnson will replace Jose Soriano (chest) on the mound in the series opener versus the A's for his second major-league start of the year. The 23-year-old Johnson has posted an inflated 15.12 ERA and 2.64 WHIP with five strikeouts over 8.1 innings in four appearances, including a start, with the Angels this season. After he was sent down to Double-A in late May, he produced a far more respectable 2.65 ERA and 0.71 WHIP with 21 punchouts over 17 frames in three starts.